U.K. Pat. No. 1,059,984 discloses 2-hydroxyalkane sulphonic acids and their salts, and their preparation from a bisulphite of a nitrogen base and an alkylene oxide such as ethylene oxide, propylene oxide or butylene oxide. The bisulphite of the nitrogen base and the alkylene oxide are water-soluble and their reaction is effected in aqueous solution.
In U.K. Pat. No. 983,049 there is disclosed a process in which epoxy compounds, including glycidyl alkyl ethers and glycidyl carboxylic acid esters, are reacted with adducts of a bisulphite with an oxo compound, e.g., 2-hydroxypropane-2-sulphonic acid, formed by reaction of sodium bisulphite with acetone. Preferred expoxy compounds are those containing 8 to 30 carbon atoms. The resulting sulphonated derivatives possess surface-active properties and are described as suitable for use as detergents and/or wetting agents. No mention is made of any epoxy compounds containing more than one epoxy group per molecule.
U.K. Pat. No. 1,310,672 describes a process for sulphonating alkyl or polyoxyalkylene glycidyl ethers by reaction with an organic carbonyl bisulphite adduct at an initial pH of from 6 to 8 and at elevated temperature. The bisulphite adduct is formed by reaction of sodium bisulphite with an aqueous aldehyde or ketone, preferably acetone. The resulting sulphonates are surfactants useful as ingredients of detergents and other washing compositions.
The three U.K. patents referred to above all relate to sulphonation of epoxy compounds containing a single epoxy group per molecule. U.K. Pat. No. 1,530,649 discloses sulphonation of a copolymer of an ethylenically unsaturated monomer, such as styrene or methylmethacrylate, with a glycidyl ester of an .alpha.-unsaturated carboxylic acid, such as glycidyl acrylate or glycidyl methacrylate. Sulphonation is achieved by reaction of the polymer in aqueous medium with sulphite ions of a water-soluble inorganic sulphite, e.g., sodium sulphite. Phase separation exists between the epoxy group-containing polymer and the aqueous solution, so sulphonation is effected in the presence of an ionic surface active agent, preferably a quaternary ammonium salt, e.g., tetra-n-butyl ammonium bisulphate, bromide, chloride or iodide. Reaction of the epoxy groups is slow and may be incomplete. Thus in the first example after 6 hours only 50% of epoxy groups had been converted to sulphonate groups, in the second example after 7 hours 96% had been converted, and in the third example after 4 hours 62% had been sulphonated. The resulting sulphonated polymers are soluble or dispersible in water and have potential application as thickeners, impregnating materials, binders, surface coating materials, adhesives, antistatic agents, ion-exchange resins and polymeric catalysts.